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Serotonergic innervation of the amygdala is increased in autism spectrum disorder and decreased in Williams syndrome.
BackgroundWilliams syndrome (WS) and autism spectrum disorder (ASD) are neurodevelopmental disorders that demonstrate overlapping genetic associations, dichotomous sociobehavioral phenotypes, and dichotomous pathological differences in neuronal distribution in key social brain areas, including the prefrontal cortex and the amygdala. The serotonergic system is critical to many processes underlying neurodevelopment and is additionally an important neuromodulator associated with behavioral variation. The amygdala is heavily innervated by serotonergic projections, suggesting that the serotonergic system is a significant mediator of neuronal activity. Disruptions to the serotonergic system, and atypical structure and function of the amygdala, are implicated in both WS and ASD.MethodsWe quantified the serotonergic axon density in the four major subdivisions of the amygdala in the postmortem brains of individuals diagnosed with ASD and WS and neurotypical (NT) brains.ResultsWe found opposing directions of change in serotonergic innervation in the two disorders, with ASD displaying an increase in serotonergic axons compared to NT and WS displaying a decrease. Significant differences (pâ<â0.05) were observed between WS and ASD data sets across multiple amygdala nuclei.LimitationsThis study is limited by the availability of human postmortem tissue. Small sample size is an unavoidable limitation of most postmortem human brain research and particularly postmortem research in rare disorders.ConclusionsDifferential alterations to serotonergic innervation of the amygdala may contribute to differences in sociobehavioral phenotype in WS and ASD. These findings will inform future work identifying targets for future therapeutics in these and other disorders characterized by atypical social behavior
Feeding Programs for Newly Arrived or Recently Weaned Calves
Fall is a stressful time for calves. They are generally weaned at this time. Following weaning, they are often transported or moved to a sale barn or unfamiliar facility. Upon arrival, they may be mixed with other cattle, subjected to processing and forced to eat unfamiliar feeds. In addition, all of these stresses may be compounded by foul weather. To combat the negative impacts of stress cattlemen should strive to get new calves on feed as rapidly as possible. Proper nutrition and a consistent health program are essential when starting calves on feed. Proper nutrition is important from two standpoints. First, the success of any health program is highly dependant on the nutritionals status of the calf. In order for the immune system of the calf to form antibodies in response to vaccination programs, sufficient protein, energy vitamins and minerals must be available. The second reason is more obvious. The calf simply needs to consume feed in order to grow and thrive. Ownership and facility costs are generally high. Feeder cattle need to gain weight in order to make money for cattlemen. Newly arrived or recently weaned calves do not readily eat upon arrival in a feedlot. Texas data (Hutcheson, 1980) suggests that a surprisingly high percentage of cattle do not eat during the first few days in the feedlot. Table 1 shows that on day one in the feedlot, only 21.7% of the cattle eat. On day three, over 40% of the cattle will not eat. On seven, 30% of the cattle will not eat. And on day 10, an average of 15% of the cattle will not eat. These data suggest that getting cattle started on feed is a major problem. Three problems need to be addressed in order to get cattle started on feed. First, recently weaned or newly arrived cattle will generally not recognize the feed bunk and may not recognize water troughs. Second, new cattle may not recognize the feed that the producer wishes to feed him. Finally, feed intake by new cattle will likely be low due to stress. The remaining section of this paper focus on managing around these problems. Additional sections include discussions of feed additives, commercial receiving, or weaning rations and health programs
Explicit lower and upper bounds on the entangled value of multiplayer XOR games
XOR games are the simplest model in which the nonlocal properties of
entanglement manifest themselves. When there are two players, it is well known
that the bias --- the maximum advantage over random play --- of entangled
players can be at most a constant times greater than that of classical players.
Recently, P\'{e}rez-Garc\'{i}a et al. [Comm. Math. Phys. 279 (2), 2008] showed
that no such bound holds when there are three or more players: the advantage of
entangled players over classical players can become unbounded, and scale with
the number of questions in the game. Their proof relies on non-trivial results
from operator space theory, and gives a non-explicit existence proof, leading
to a game with a very large number of questions and only a loose control over
the local dimension of the players' shared entanglement.
We give a new, simple and explicit (though still probabilistic) construction
of a family of three-player XOR games which achieve a large quantum-classical
gap (QC-gap). This QC-gap is exponentially larger than the one given by
P\'{e}rez-Garc\'{i}a et. al. in terms of the size of the game, achieving a
QC-gap of order with questions per player. In terms of the
dimension of the entangled state required, we achieve the same (optimal) QC-gap
of for a state of local dimension per player. Moreover, the
optimal entangled strategy is very simple, involving observables defined by
tensor products of the Pauli matrices.
Additionally, we give the first upper bound on the maximal QC-gap in terms of
the number of questions per player, showing that our construction is only
quadratically off in that respect. Our results rely on probabilistic estimates
on the norm of random matrices and higher-order tensors which may be of
independent interest.Comment: Major improvements in presentation; results identica
Obstetric and Perinatal Outcomes in Type 1 Diabetic Pregnancies: A large, population-based study
The aim of this epidemiological study was to elucidate whether in recent years, obstetric and
perinatal outcomes in pregnancies complicated by type 1 diabetes (T1DM) have improved or
not. The objective was also to identify possible risk factors for adverse outcome for the
mother, fetus and the newborn. All studies (Î-ÎV) included in this thesis were based on
national data from the Swedish Medical Birth Registry, during the time period 1991-2007.
In 5,089 type 1 diabetic pregnancies and 1.2 million controls we found significantly increased
risks of all adverse outcomes in women with T1DM: adjusted odds ratios: severe
preeclampsia: 4.47 (3.77-5.31), Caesarean delivery: 5.31 (4.97-5.69), stillbirth: 3.34 (2.46-
4.55), perinatal mortality: 3.29 (2.50-4.33), major malformations: 2.50 (2.13-2.94) and large
for gestational age: LGA (birth weight â„ +2 SD): 11.45 (10.61-12.36) (study Î).
The markedly elevated odds of an LGA outcome inspired us to characterize in more detail the
distribution of birth size in a large national cohort of T1DM offspring (study ÎÎ n=3,705) and
to investigate if disproportionate body composition was associated with increased risk of
perinatal complications (study ÎÎÎ n=3,517). Percentiles for birth weight (BW), birth length
(BL) and head circumference (HC) were formed based on data from non-diabetic pregnancies
and standard deviation scores (SDS) were calculated for BW, BL and HC. The ponderal
index (PI: BW in grams/(BL in cm) Âł was used as a proxy for body proportionality and fat
mass and we defined disproportionate/overweight LGA as infants with a BW and PI â„90th
percentile for gestational age and gender.
The distributions of BW, BL and HC were all unimodal but significantly shifted to the right of
the normal reference. The distribution for BW was most markedly shifted to the right. 47%
were LGA with a BW â„90th adjusted percentile. The mean ponderal index (PI) was
significantly increased and 46% of LGA infants were disproportionate with a PI â„90th
percentile and thus overweight at birth. A novel and unexpected finding was that fetal
macrosomia was more pronounced in preterm and female infants (study ÎÎ). Surprisingly,
neonatal outcome was independent of body proportionality in appropriate for gestational age
(AGA) and LGA infants. The risk of adverse outcome was significantly increased in LGA
compared with AGA infants born at term (study ÎÎÎ). There was a significant interaction
between gestational age and body weight with prematurity overriding LGA as a risk factor for
neonatal morbidity in moderately preterm infants.
In study ÎV, we examined the risk of adverse outcome in relation to pre-pregnancy body mass
index in a national cohort of 3,457 T1DM pregnancies compared to 764,498 non-diabetic
pregnancies. Maternal overweight/obesity increases the risk of adverse outcome in both
women with and without T1DM. Within the T1DM cohort, obesity was associated with
increased odds of major malformations adjusted OR: 1.77 (1.18-2.65) and preeclampsia
adjusted OR: 1.74 (1.35-2.25). T1DM was a significant effect modifier of the association
between BMI and major malformations, preeclampsia, LGA and neonatal overweight.
Conclusion: In spite of major improvements in the management of type 1 diabetic pregnancies
over the years, the present findings clearly demonstrate that T1DM pregnancies still are
associated with significantly increased risk of adverse outcomes. An important observation is
the rising incidence of LGA infants, which partly can be attributed to a concomitant increase
in maternal BMI. This development is worrying as LGA infants face an excess risk of both
perinatal and future complications as compared to normal sized infants. The novel and
unexpected finding of a gender difference in fetal macrosomia requires further investigations
Dose verification of dynamic MLC-tracked radiotherapy using small PRESAGE (R) 3D dosimeters and a motion phantom
With the increasing complexity of radiotherapy treatments typical 1D and 2D quality assurance (QA) detectors may fail to detect out-of-plane dose discrepancies, in particular in the presence of motion. In this work, small samples of the PRESAGEÂź 3D radiochromic dosimeter were used in combination with a motion phantom to measure real-time multileaf collimator (MLC)-tracked radiotherapy treatments. A different sample of PRESAGEÂź was irradiated for each of three different irradiation scenarios: (1) static: static sample, without tracking (2) motion: moving sample, without tracking and (3) tracking: moving sample, with tracking. Our in-house software DynaTrack dynamically moves the linac's MLC leafs based on the target position. The doses delivered to the samples were reconstructed based on the recorded positions of the MLC and phantom during the beam delivery. PRESAGEÂź samples were imaged with an in-house optical-CT scanner. Comparison between simulated and measured 3D dose showed good agreement for all three irradiation scenarios (static: 99.2%; motion: 99.7%; tracking: 99.3% with a 3%, 2 mm and a 10% threshold local gamma criterion), failing only at the edges of the PRESAGEÂź samples (~ 6 mm). Given that the dose distributions deposited using the DynaTrack system have been independently verified, this experiment demonstrates the ability of PRESAGE to measure 3D doses correctly in a tracking context. We conclude that this methodology could be used in the future to validate the delivery of dynamic MLC-tracked radiotherapy
The Vascularization of the Skin of the Atlantic Hagfish, Myxine glutinosa L. as Revealed by Scanning Electron Microscopy of Vascular Corrosion Casts
The vascularization of three different (A, B, C) skin regions (from the level of the heart to the cloaca including dorsal, lateral and ventral skin areas) of the Atlantic hagfish, Myxine glutinosa L. was studied by scanning electron microscopy of vascular corrosion casts. Vessel variables were measured either from semithin sections (diameters) or from vascular corrosion casts (diameters, lengths) and total blood capacities as well as vessel surfaces per unit skin area (mm2) were calculated. There are no significant differences in the number of subepidermal capillary meshes (ranging from 164 to 185 meshes per micrograph) in areas A, B or C nor in vessel lengths. The average vessel length per mm2 is 32 mm. Assuming an average diameter of 22.3 ÎŒm these vessels have an average surface of 2.24 mm2 and a volume of 12.5 nanoliters (nl). In contrary weighing two pieces ( 5 mm times 5 mm in size) of the whole skin vascular bed - knowing the density of the casting medium -results in only one fifth of that volume. Overestimation of vessel lengths and diameters by measuring casted structures from micrographs on the one hand and inaccuracies in weighing or dissection of casted skin pieces on the other hand are discussed as sources of observed differences
Weak and Strong coupling regimes in plasmonic-QED
We present a quantum theory for the interaction of a two level emitter with
surface plasmon polaritons confined in single-mode waveguide resonators. Based
on the Green's function approach, we develop the conditions for the weak and
strong coupling regimes by taking into account the sources of dissipation and
decoherence: radiative and non-radiative decays, internal loss processes in the
emitter, as well as propagation and leakage losses of the plasmons in the
resonator. The theory is supported by numerical calculations for several
quantum emitters, GaAs and CdSe quantum dots and NV centers together with
different types of resonators constructed of hybrid, cylindrical or wedge
waveguides. We further study the role of temperature and resonator length.
Assuming realistic leakage rates, we find the existence of an optimal length at
which strong coupling is possible. Our calculations show that the strong
coupling regime in plasmonic resonators is accessible within current technology
when working at very low temperatures (<4K). In the weak coupling regime our
theory accounts for recent experimental results. By further optimization we
find highly enhanced spontaneous emission with Purcell factors over 1000 at
room temperature for NV-centers. We finally discuss more applications for
quantum nonlinear optics and plasmon-plasmon interactions.Comment: published as Phys. Rev. B 87, 115419 (2013
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